Valve trains of a generic type in which the lift of the gas exchange valve is the result of the superposition of a mechanical lift caused by the cam and a variably adjustable lift of a hydraulic lifting device that acts independently of the cam on the movement of the gas exchange valve, are known in the prior art. Thus, for example, DE 101 56 309 A1 describes a cup tappet valve train comprising a hydraulic lifting device. This comprises a pressure piston that is arranged between in inner side of the cup bottom and the valve stem and actuates the gas exchange valve relative to the cup tappet as a function of the change of volume of a pressure chamber defined by the pressure piston. The pressure chamber, in its turn, is connected through channels in the interior of the cup tappet and in the tappet guide of the internal combustion engine to a hydraulic medium supply whose pressure and volume stream can be adjusted in conformance with the point of operation.
As alternatives to the aforesaid cup tappet, the cited document proposes further force transmission devices that are known to the person skilled in the art on the one hand, as stationary support elements arranged in the internal combustion engine for mounting a tilting valve lever and, on the other hand, as a tappet, for example, of a pushrod valve train, guided longitudinally in the internal combustion engine for loading valve levers. Insofar, the aforesaid document does not provide any incentives that would occasion a person skilled in the art to also apply such hydraulic lifting devices in valve train architectures other than those named above.